How to Check Number/ Letter Peoplecode

How to Check Number/ Letter Peoplecode function from input value. You can use this peoplecode function at below.

Function Check_Number(&STR) Returns boolean;
   &LEN = Len(&STR);
   If &LEN = 0 Then
      Return False;
   End-If;
   For &I = 1 To &LEN;
      &CODE = Code(Substring(&STR, &I, 1));
      If (&CODE < 48 Or
            &CODE > 57) Then
         Return False;
      End-If;
   End-For;
   Return True;
End-Function;

Function Check_Letter(&STR) Returns boolean;
   &LEN = Len(&STR);
   If &LEN = 0 Then
      Return False;
   End-If;
   For &I = 1 To &LEN;
      &CODE = Code(Upper(Substring(&STR, &I, 1)));
      If (&CODE < 65 Or
            &CODE > 90) Then
         Return False;
      End-If;
   End-For;
   Return True;
End-Function;

Function Check_Number(&STR) Returns boolean;

&LEN = Len(&STR);

If &LEN = 0 Then

Return False;

End-If;

For &I = 1 To &LEN;

&CODE = Code(Substring(&STR, &I, 1));

If (&CODE < 48 Or

&CODE > 57) Then

Return False;

End-If;

End-For;

Return True;

End-Function;

Function Check_Letter(&STR) Returns boolean;

&LEN = Len(&STR);

If &LEN = 0 Then

Return False;

End-If;

For &I = 1 To &LEN;

&CODE = Code(Upper(Substring(&STR, &I, 1)));

If (&CODE < 65 Or

&CODE > 90) Then

Return False;

End-If;

End-For;

Return True;

End-Function;

Reference :http://www.compshack.com/peoplecode/peoplecode-check-number-and-check-letter-functions#comment-4979